Why did Qin Feng in Detective Chinatown achieve a perfect crime?

This movie tells us why Qin Feng, the protagonist, wants to complete a perfect crime. It was because my father was caught committing a crime when I was a child that I planted a seed in the heart of young Qin Feng. Later, his single-parent family also created his introverted personality, especially though he didn't commit a crime, he spared the real criminals in the first Thai movie or the second American movie. Actually, isn't this a crime?

At the beginning of the first film, Qin Feng told the police instructor that the purpose of being a policeman is to "complete a perfect crime", which made everyone very confused. Then Sino folded the paper in half and stood on the table. You can clearly see that the paper is divided into two sides, one representing evil and the other representing good, while Qin Feng, as a detective, is the bisector, which keeps the balance between the two. Si Nuo's "The Last Laughter" sublimated the film and brought the ideology to a deeper level.

Why did Qin Feng complete a perfect crime? This is not mentioned in the second part, but in the first part, we just turn the camera to the scene when Qin Feng's father was caught, which is even more thought-provoking. Normal logic, or normal people will never inexplicably have the idea of completing a perfect crime when they see their father being caught. However, Qin Feng thought so, and at the beginning of the first plot. In the end, the general reasoning story will tell whether the protagonist who solved the case gradually introspects whether he can keep his original intention from becoming such a person because he has seen too many high-intelligence criminals commit crimes, or whether the protagonist gradually becomes such a person in order to catch up with these high-intelligence criminals by constantly exploring their ways of thinking, so that the theme can be sublimated.

Why does Qin Feng want to achieve perfect crime? In my opinion, this must be due to the influence of his father's arrest on him, but it should be more than that. Qin Feng is a very clever man, which is reflected in his super talent in finding crimes, and also in committing crimes. Whether such people are troubled by crime or stop committing crime is a common setting in detective novels.